title: Recent temporal trends in sleep duration, domain-specific sedentary behaviour and physical activity. A survey among 25-79-year-old Danish adults.
abstract: BACKGROUND
  Prevalence of sedentary behaviour is high in many countries, but little is known about temporal trends in sitting time.
  
  
  OBJECTIVE
  To examine temporal changes in sleep and domain-specific sedentary behaviour and moderate to vigorous leisure time physical activity (MVPA).
  
  
  METHODS
  Two cross-sectional population-based surveys of 25-79-year-old inhabitants were conducted in The Capital Region of Denmark in 2007 (N = 69.800, response rate 52.3%) and 2010 (N = 77.517, response rate 54.8%). Information on sedentary behaviour and physical activity was obtained from self-report questionnaire and sociodemographic information from central registers. Data were weighted for survey design and for non-response and were analysed by multiple regression analyses.
  
  
  RESULTS
  In 2007, the entire survey population reported a mean daily sleeping duration of 7.4 hours, leisure time sitting of 3.4 hours per day, occupational sitting of 4.4 hours per day, MVPA of 0.87 hours per day and a total 24-hour energy expenditure of 40.12 METs per day. In 2010, duration of sleep was unaltered (p = 0.1), sedentary leisure time and sedentary work time had increased by 12.6 minutes (p < 0.0001) and 13.2 minutes (p < 0.0001) per day, respectively. Time spent on MVPA had increased by 2.9 minutes per day (p < 0.0001). The 24-hour energy expenditure had decreased by 0.41 METs (p < 0.0001).
  
  
  CONCLUSIONS
  Adult Danish men and women spend an increased amount of time sitting down at work and during leisure time, but also on leisure time MVPA. As duration of sleep is unaltered findings suggest that low intensity physical activity may be displaced in everyday life.
authors.affiliation: 1Research Centre for Prevention and Health, The Capital Region of Denmark, Glostrup University Hospital, Glostrup, Denmark.
authors.forename: Mette
authors.initials: M
authors.lastname: Aadahl
authors.forename: Anne Helms
authors.initials: AH
authors.lastname: Andreasen
authors.forename: Lene
authors.initials: L
authors.lastname: Hammer-Helmich
authors.forename: Lone
authors.initials: L
authors.lastname: Buhelt
authors.forename: Torben
authors.initials: T
authors.lastname: Jørgensen
authors.forename: Charlotte
authors.initials: C
authors.lastname: Glümer
mesh_terms: D000328:Adult; D000368:Aged; D003430:Cross-Sectional Studies; D003718:Denmark; D004651:Employment / Q000706:statistics & numerical data*; D005260:Female; D006801:Humans; D007899:Leisure Activities / Q000523:psychology*; D008297:Male; D008875:Middle Aged; D009043:Motor Activity / Q000502:physiology*; D057185:Sedentary Behavior; D012890:Sleep; D011795:Surveys and Questionnaires; D013997:Time Factors
keywords: Exercise; population survey; sedentary behaviour; temporal trends